A wireless sensor network (WSN) is a network of wireless nodes equipped with sensors to monitor physical or environmental conditions, such as temperature, air pressure, flow rate, sound pressure, etc. A wireless node transmits the data collected by its sensor to a destination. In an example, the wireless node may pass the data to another wireless node that is “closer” (either physically or logically) to the destination than the originating wireless node; this process continues until the data is delivered to the destination.